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Nanosensors for Industrial Applications
Published in Vinod Kumar Khanna, Nanosensors, 2021
It is a vibratory gyroscope in which a vibrating CNT is used to determine the angular rate. The field emission property of CNT is utilized for measuring frequency and amplitude of the vibration. Changes occurring in vibrational parameters due to rotation help in deduction of the angular rate. Field emission, also called cold emission, is actually high-field electron emission, entailing the extraction of electrons from a surface by application of a large electrostatic field. The phenomenon facilitating this extraction is tunneling of electrons through the surface potential barrier. CNTs are bestowed with exceptional physical and chemical properties. Possession of these properties favors field emission from CNTs. The CNTs are mechanically strong. They also display high chemical stability. In addition, they have nanoscale diameters and long lengths, resulting in high width-to-height or aspect ratios. The CNT gyroscope offers advantages of low energy consumption. It is also capable of high resolution and can provide a large scale of measurement.
Picometer Detection by Adaptive Holographic Interferometry
Published in Klaus D. Sattler, Fundamentals of PICOSCIENCE, 2013
Martin, G.L. and P.R. Schwoebel. 2007. Field electron emission images of multi-walled carbon nanotubes. Surf. Sci. 601: 1521-1528.
Infrared rectification based on electron field emission in nanoantennas for thermal energy harvesting
Published in Journal of Modern Optics, 2020
A. Chekini, M. Neshat, S. Sheikhaei
It can be seen in Figure 3 that the maximum field enhancement is achieved at the designed wavelength of 10 µm. For the field electron emission modelling, as mentioned before, the Fowler-Nordhiem theory was used. In this theory field electron emission process and the electron tunnelling from top of the vacuum-metal potential barrier is modelled. The total current from the tip of the cathode in the presence of an electric field is given by (32,33) where E is the electric field intensity, ϕ is the work function in eV and aFN, bFN are Fowler-Nordhiem constants, and are calculated as where e denotes the electron charge, me is the electron mass, and hp is the Planck’s constant.